In article ,
osspam says...


I have to pressure clean my driveway. It is stained brown from years of
well water overflow. I understand that using a water pressure machine and
muriatic acid is good for this type of cleaning

Let's consider a slower acting acid with less tendency to etch the concrete,
like oxalic acid, the main component of commercial auto radiator flushing
compounds. All you want to do is remove the stains, so any mild acid that
converts the iron stains to a soluble form should be a candidate. For now,
buy
a can of radiator flush and apply a paste of it to see how long it takes to
have an effect, then go for a larger size if it responds. There may also be
industrial compounds from, typically, janitorial supply stores or
McMaster-Carr, Graingers or similar. Do your research, then decide. Good
luck.

Joe


Rustoleum has a new product out that claims to be fumeless, and
quicker. I 've never tried it, but I would look into it.

Dennis